THE IMPACT OF SEASON OF BIRTH AND AGE OF BOARS OF POLISH LANDRACE BREED ON BREEDING OPERATION RESULTS

Abstract

The aim of the study was to assess the impact of season of birth and breeding of boars of Polish Landrace breed on their insemination efficiency. The study material consisted of 35 589 ejaculates collected between 1994-2013 from 330 of Polish Landrace breed boars farmed in Maopolska Biotechnology Centre, the Examination Station of Boars in Czermin. Ejaculates were marked with: volume of ejaculate, without spermatozoid fraction, percentage of progressive spermatozoids, concentration o spermatozoids, the general number of spermatozoids in the ejacu- late, number of insemination doses and value of one ejaculate. The conducted studies demonstrate a significant impact of interaction between the season of birth and the age of boar in the process of development of all the physical parameters of semen in Polish Landrace breed boars. The studies have shown that the highest reproduction potential, demonstrated with the number of insemination doses collected (26.96), was found in the oldest boars born during summer season. The results of studies indicate that quantitative and qualitative parameters of semen of the Polish Landrace breed boars mainly depend on their age. The highest variability affecting the characteristics of ejaculates, resulting from the effect of boars' age, was found for the ejaculate vo- lume of (86.14%), whereas impact of birth season was marked by the percentage of spermatozoids with inferior changes (61.64% of the variability).